Work on the contract, announced Friday by the Department of Defense, includes manufacturing and testing of Mk 21 mod 2 and Mk 21 mod 3 canisters. The canisters help contain exhaust gas and provide a launch rail while firing the missile, and function as shipping containers as well.

The canisters also serve as missile shipping and storage containers. The work mandated by the contract modification will run through August 2021.

The Mk 41 is a modular missile launch system capable of fielding anti-aircraft, anti-surface and ballistic missile defense missiles. The modules can be linked together, allowing different ship classes to carry the number of missiles needed for their class capabilities and requirements.

It is the missile launch system on the U.S. Navy's Ticonderoga-class cruisers and Arleigh Burke-class destroyers along with different ships deployed by allied nations such as Japan, the United Kingdom and others.

The VLS can fire the Standard series of surface-to-air missiles and anti-ballistic missile interceptors like the SM-3, Tomahawk land attack cruise missiles, and other weapons such as ESSM point defense missiles and ASROC anti-submarine rocket propelled torpedo launchers.